This invention pertains to wood graining tools and, more particularly, to tools which are particularly designed to effectively simulate the grain patterns of variously sawn woods.
The annular growth rings of trees display primary grain patterns according to the method utilized in sawing the wood. Thus, the resulting grain patterns of plain sawn, quarter sawn and rotary cut woods will vary in their display. Accordingly, it is desirable to produce wood graining tools which can easily simulate these various graining patterns. A method of wood graining is described in my 1981 Basic Wood Graining Oak which is hereby incorporated by reference herein.
The Briggs U.S. Pat. No. 3,843,992 discloses a wood graining tool with a well-known corrugated pattern thereon. This pattern is said to produce a heart grain effect. A heart grain effect is characterized by a plurality of first and second veins terminating in crowns spaced along the surface. This pattern is presented by a plain sawn cut of a tree.
The Briggs device also has a comb which is drawn along the graining liquid on the application surface so as to produce a series of parallel veins which is said to simulate a quarter sawn grain pattern.
The Briggs device does not produce a rotary cut type of wood grain pattern which is characterized by an annular ring of rings appearing in the graining pattern.
One problem with past tools is that the graining patterns in the tool presented predictable and ineffectual wood grain patterns. More importantly, as these tools use a series of increasingly larger circular ribs to present the grain pattern, portions of these ribs relative to the trailing edge of the tool approach angles of 90.degree.. As such rib portions approach a parallelism to the direction of tool travel, the graining liquid on the application surface will pass between these ribs untouched. Thus, the ribs cannot effectively interface with the graining liquid on the application surface. Moreover, as the radius of the rib arcs increases along the length of the graining tool pattern, the radii of the rib arcs at the top of the tool become so large that they become ineffective to produce a proper crown of a plain sawn wood grain pattern.
As to quarter sawn woods, prior tools utilized combs having fixed teeth thereof drawn along the application surface so as to space the graining liquid thereon. The fixed relationship of the teeth hindered the variability of the resulting wood grain pattern.
Finally, in making a plain sawn cut grain pattern, i.e. a closed loop or series of closed grain loops appear in the wood grain pattern, it was necessary to slide and roll a tool along the application surface in one direction to make a first portion of the loop and then reverse the rolling motion of the tool while maintaining the forward sliding motion of the tool to present a second loop so as to close the loop. Thus, it was difficult to easily and effectively present such loops as the required rocking motion of the tool produced light and dark shades on the graining pattern as it was either lifting the liquid off the surface or depositing the liquid on the surface. Moreover, in order to apply a series of loops along an extended application surface it was necessary to roll the tool back and forth several times which aggravated the above problems.
In response thereto I have invented a wood graining tool having a plain sawn graining pattern thereon which presents a series of crown-shaped ribs having rib arcs of a constant radius. The ribs are displaced along a longitudinally extending centerline of the tool pattern. Laterally extending ribs emanate from each rib arc at an angle of 40.degree. to 50.degree. relative to the horizontal. This angular relationship affords a proper pick up and placement by the ribs of the graining liquid on the application surface. The use of rib arcs of constant radius along with the lateral ribs at selected angles present effective ribs along the entire tool length which enhance the graining liquid pick up and pattern application.
As to a quarter sawn grain pattern, my second tool presents a plurality of ribs diagonally extending across the tool and being of variously spaced distances therebetween. This rib pattern presents a continually changing number of rib contact points with the application surface so as to present a variable vein pattern when the tool is rolled along the length of the application surface.
Finally, I provide a rib pattern on a graining tool which will easily produce the loops found in a plain sawn cut wood grain pattern. My tool generally comprises a first arcuate, concave rib and a second arcuate, convex rib. Upon rolling movement of the tool in a single direction the graining liquid is efficiently directed between the ribs so as to produce an annular ring or series of rings on the application surface.
It is therefore an object of this invention to provide a wood graining tool which will provide an effective wood graining pattern corresponding to a plain sawn wood.
Another object of this invention is to provide a wood graining tool which will provide an effective wood grain pattern corresponding to a quarter sawn wood.
Still another object of this invention is to provide a wood graining tool which will provide an effective wood grain pattern corresponding to a rotary cut wood.
A still further object of this invention is to provide a wood graining tool with graining pattern thereon which is effective in graining liquid pick up, distribution and application.
Still another object of this invention is to provide a wood graining tool, as aforesaid, which provides an effective working pattern across the length and width of the wood graining tool.
Another particular object of this invention is to provide a wood graining tool with quarter sawn pattern, as aforesaid, which produces a variable quarter sawn pattern along the length of the application surface.
Still another object of this invention is to provide a wood graining tool with plain sawn cut pattern, as aforesaid, which effectively presents an enclosed loop or loops upon movement of the tool in one direction on the application surface without rocking the tool.
A still more particular object of this invention is to provide a plain sawn wood graining tool, as aforesaid, having a plurality of crown-shaped ribs thereon each comprising an arc of a constant radius positioned along a longitudinal line of the tool with ribs emanating therefrom at selected angles relative to the horizontal.
Still another particular object of this invention is to provide a quarter sawn wood graining tool, as aforesaid, which comprises a series of graining ribs extending diagonally across the tool.
Another object of this invention is to provide a tool, as aforesaid, which utilizes a selected pattern of graining ribs so as to effectively pick up and apply paint for making a closed loop found in a rotary cut or plain sawn cut wood grain pattern.
Other objects and advantages of this invention will become apparent from the following description taken in connection with the accompanying drawings, wherein is set forth by way of illustration and example, certain embodiments of this invention.